1. Field of the Invention
The present invention relates to the construction arts, and particularly to building blocks of a type that can be assembled.
2. Related Applications
Applicants previously filed application Ser. No. 09/300,364 (abandoned), which contained some of the information presented herein. Applicants do not claim priority based upon application Ser. No. 09/300,364.
3. Description of the Related Art
The contemporary demands on the design and construction arts remain the elemental ones: to avoid discomforts caused by excesses of heat or cold or by intrusions of rain, wind, fire or vermin; to be durable, sturdy, and easily maintained; and to be pleasing and attractive in appearance.
Early civilizations recognized stone as a most desirable construction material. When available, stone was incombustible, impenetrable by then-known weapons, could be expected to endure, and could be shaped into usable form. The use of stone diminished over time due to development of other materials that were more amenable to fabrication and assembly in our industrialized era.
In the 19th century, it was discovered that concrete block “stones” having larger overall dimensions could be made and easily handled when the blocks were vertically hollowed, thus reducing weight and providing adequate bearing strength for the erection of structures. These concrete blocks have traditionally and customarily been erected by use of mortar being placed between adjacent block surfaces, which practice demands the highly trained, and relatively expensive skills of the masonry artisan. Thus, with the relative cost of constriction becoming an element of increasing concern, the use of masonry materials declined significantly over the past decades.
Additionally, the relatively recent increase in awareness of the need for conserving energy and natural resources, and reducing noise and noxious pollution, has accelerated the demand for improvements in construction techniques and materials.
The use of building blocks in the construction art is well established. The blocks, usually of concreted material, are precast at a manufacturing facility, and subsequently transported to a construction site. For erection of walls, building foundations, fences, noise barriers, and like structures, the blocks are placed in end-to-end alignment in rows, commonly referred to as courses. The first course is generally placed upon a pre-prepared base. A second course is placed in staggered alignment upon the first course. Additional courses are added until the desired height of the structure is achieved. The courses are staggered so that the abutment between the two adjacent blocks is approximately centered over a single block of a successively lower course.
Those blocks that are utilized in the centers of courses, and which constitute the majority of block configurations, are customarily referred to as stretchers. Those blocks that are utilized at the ends of courses, such as at wall corners and door or window openings, are customarily referred to as end stretchers. And where required by design dimension constraints or at certain wall end locations, blocks of approximately one-half the length of stretchers are utilized, and are customarily referred to as half blocks.
Reduction of construction costs may be realized by utilization of concrete building block components which do not require the high cost and rarely available skills of the masonry artisans. A mortarless, or “dry stacked,” concrete building block design addresses this required cost effectiveness.
A review of known prior art discloses a number of designs of interlocking and mortarless building block designs which have universally failed to gain widespread acceptance by the public, the architectural designers, or the constructors. Many of these building block designs are highly complex, and require completely new and expensive fabrication equipment to manufacture. Additionally, the more complex the design, the greater care must be exercised in handling of the blocks, and the greater the irreparable damage in transit and at the erection site, all of which render these blocks to be expensive.
These known prior art designs universally provide straight linear horizontal paths, or slightly offset linear horizontal paths, through the blocks for the unrestricted transmission by conduction of thermal and acoustic energy. The addition of externally installed thermal and acoustic insulating materials is required in order to achieve the desired insulating characteristics in finished structures, which may result in higher construction costs.
Some of the prior alit designs are incompatible with traditional conventional construction systems and materials, thus rendering them unacceptable for renovation rehabilitation, or expansion construction of existing structures.
There exists a need for a construction block which may reduce the cost associated with the erection of high quality, long lasting structures, which may provide significant thermal and acoustic insulation qualities, which may be assembled by semi-skilled labor, which may be strengthened to withstand extreme wind, earthquake, and similar natural phenomena, which may have improved lateral strength and stability, of erected strictures, which may be rot, rust and vermin proof, which may be compatible with a wide range of architectural aesthetic treatments, and which largely may be produced by existing manufacturing equipment.